Tablets such as Apple's iPad aren't just a post-PC device: they're a pre-PC one too, used by people in the mornings around breakfast time and then later in the evening, after they use with their PC in the day, according to research from comScore.

And the UK is in the vanguard of adoption of non-PC devices such as mobiles, tablets and games consoles for browsing the web, ranking with the US second only to Singapore in the use of the new devices for browsing the web.

Although tablet browsing is still only a tiny slice of overall browsing, together with smartphones they are a fast-growing segment of the browsing market, the research found.

The comScore research also found patterns of usage were different throughout the day depending on the device being used: during weekdays, tablet traffic had a morning peak at about 8am before falling off and then rising again from 4pm onward until it hit a daily peak at 10pm – suggesting that people were using them at home, possibly while watching TV.

For smartphones, there was a similar 8am peak and a smaller fall which then also rose to a 10pm peak, though without such a large fall during the day – suggestive of people using them as a device they carry with them everywhere.

PCs, meanwhile, have a peak in web browsing at 9am which then fell steadily through the day.

Variation in US web traffic by source to news sites during the week. Data and graphic: comScore

At the weekend, the usage pattern in the US is much steadier, with tablets, mobiles and PCs all seeing a peak at 9.30am and tailing away, with a second peak at about 9.30pm for PCs and around 10pm for tablets.

Variation in US web traffic by source to news sites during the weekend. Data and graphic: comScore

The study, carried out in August and September, gathers data from site access by devices as well as other information gathered by the company.

In the UK and US, 6.8% of web browsing comes from non-PC sources. Singapore, which leads the world, has 7.2% of web browsing coming from non-PC devices.

In the UK, 67.6% of non-PC web browsing was from mobiles, 24.7% by tablets and 7.7% by other devices such as games consoles and e-readers. In the US the figure was 64.4%, 28.1% and 7.5%.

That means in the UK and US about 4% of overall web browsing comes via smartphones and 1.6% from tablets. While small, they also indicate rapid growth in a markets which barely existed four years ago. The iPhone first went on sale in mid-2007, while the first Android phones were not available until the end of 2008. The iPad only became available in the UK in May 2010; since then about 40m iPads have been sold worldwide, with the number of tablets including Android models in use probably at 50m.

That compares to an installed base of around 1.5bn PCs worldwide. Estimates for the number of smartphones in use worldwide are between 600m and 800m, depending on replacement speed.

The comScore figures might imply at first that tablets are under-represented in web viewing, as the number in use is equivalent to 2.6% of the number of installed PCs. Similarly, there are nearly half as many smartphones as PCs in use.

But instead the figures appear to point to the way that people are jumping between devices – and especially to the way that tablets have begun to be used at the beginning and end of the day instead of a PC.

Thus tablet owners use their devices to browse news websites at the start of the day, and then move on to a PC during the working day, and then back to a tablet at the end of the day. Similarly, mobile phones may be used for web browsing through the day when people are away from a PC.

The growth of tablet use is borne out by the fact that even as non-PC traffic grew over the past four months, the proportion from tablets rose within it from around 20% to 30%. Meanwhile smartphones were pushed down, as were games consoles and e-readers, even though usage increased.

"While tablets have thus far only penetrated a small percentage of the US population, the potential for this device to break into the mainstream is significant, as more manufacturers offer tablets at varying price points," comScore notes.

"Currently, half or more of tablet users report having engaged in activities such as consuming news, viewing entertainment, social networking, and shopping on their devices at least once in the previous month. With more publishers optimising their properties for tablet presentation and developers creating apps specific to tablets, it is likely that tablet owners' engagement with their devices will only continue to grow."

Overall, comScore says the patterns are indicative of a new, global breed of "digital omnivores" who consume internet content across a multitude of devices through the day. In five global markets – the UK, US, Australia, Japan and Singapore – more than 5% of internet traffic came from non-PC devices.

The increase in Wi-Fi availability in places such as coffee shops and some food outlets is also helping drive that use, with 37.2% of US digital traffic coming from mobile phones using a Wi-Fi connection. Yet tablets – commonly used with a Wi-Fi connection – were increasingly seen accessing the net via mobile broadband, with just less than 10% of connections coming on the move.

In all, the US mobile population grew 19% to 116m users – compared to around 260m of the total population in the US – whose use of mobile media is being driven by smartphones. Of those, half use "mobile media" via the web; the others use a mixture of voice and texting.

Tablets – principally the iPad – are growing rapidly in use, the report found. "Although tablets have yet to be widely adopted, they already contribute nearly 2% of all US web browsing traffic, driven almost exclusively by the iPad, which currently accounts for more than 97% of all tablet traffic," the company said.

Apple devices were also used disproportionately to their installed base, said comScore: Apple's iOS runs 43.1% of the smartphones and tablets in use in the US, compared to 34.1% for Android devices and 15.4% for BlackBerry maker RIM.

But in browsing, iOS makes up 58.5% of the use, against 31.9% for Android and 5.0% for RIM – suggesting iOS users browse about 36% more than expected, Android users 6.5% less, and BlackBerry users only one-third as much.

US tablet ownership was concentrated among young males, with half being used in households earning $100,000 (£63,000) and above, the research found, though the expectation is that the Amazon Kindle Fire, priced at $199 against the iPad's $399, will broaden tablet adoption.

Content availability was also important: half of tablet users had made a purchase via a tablet in the past month, the study found.